Power actuated shaver



June 23, 1,941 :Hp J. zlMMERM-ANN 2,237,337-

POWER Ac'rATEn-SHAVER l Filed Marchal, -1940 2 sheets-sheet 1 Hans zmmermamg Patented June 23, A1942 POWER CTUATED SHAVER I I-Ians J. Zimmermann, Philadelphia, Pa., 'assignor of one-half to Kern Dodge, Philadelphia, Pa.

Appiieation March 21, 1940, serial No. 325,147

2 Claims.

'Ihis inventionhas general reference to poweractuated razors and more particularly to the species commonly known as dry shavers which are adapted for use without the aid of a lather or cream. In such shavers, removal of the hair is usually veffected by rapid reciprocation of the cutter blade relative to a stationary blade or comb, and, while such means have attained a measure of popularity, they possess one serious disadvantage, namely that'due to the rapid reciprocation of the cuttingblade over the gaps between the teeth in the comb, such movement prevents the hair from proper erection, or straightening up, between the comb'teeth, with the result the user must employ many strokes to ensure a clean shave.

The primary object of this invention is to overcome the above noted disadvantage by reciprocation of the cutter blade with definite dwell periods which augment the time for beard erection over all known types of dry shavers,

Another object is the provision of a motoroperated dry shaver, the power shaft whereof is equipped with a novel form of cutter blade actuating cam designed to permit gradual acceleration of blades after the dwell period, and its deceleration to such dwell period, both of which are effected during definite rotary movements ofthe power shaft. In other words, the actuating cam of this invention is preferably contoured as to dene for each half-revolution of the power shaftv a 30 dwell angle, a 60 accelerating angle, followed by a 60 decelerating angle and a 30-dwell angle during each stroke of the cutting blade.

A further object is the provision of a motionactuator cam for the'cutting blade of power op-` erated dry shavers which enables reduction in theA motor speed necessary, as compared with analogous types of shavers, whereby thelife of said cutting blade, as well as that of the motor, is appreciably increased.

Other objects and ancillary advantages will hereinafter appear, or become apparent, from the following description of typical adaptations of the present invention considered in conjunction with the accompanying sheets of drawings,

. whereinlike characters of reference are applied to corresponding parts in therespective views;

still larger scale, the novel actuator cam of this invention and the` coactive 4end of the cutter blade operating member in the dwell position 'the respective parts in the active position.

Fig. 5 is a fragmentary detail section of the stationary and movable cutter elements.

Fig. 6v is a broken view, similar to Fig. 1, showing the adaptation of this invention to another type of dry-shaver.

Fig. 'l is a many-times enlarged scale section on the plane VII-VII of Fig. 6.

Fig. 8 is a further enlarged scale section on the plane VIII-VIII of Fig. 6; and,

Fig. 9 is a diagram illustrating the movement imparted to the cutting blade relative to the stationary blade, as effected by the novel actuator cam means of this invention.

Referring more in detail to the drawings, and rst to the embodiment shown by Figs. 1-5, inclusive, the reference I comprehensively designates the hollow body portion of a known type d'ry shaver, the same including an electro-magnet 2 served with current through a pair of contact prongs 3; and having an associated stator or eld 4, with a rotor or armature 5 and drive shaft 6, said drive shaft being journaled in a yoke 1, of insulate material and having an initiator or starting disc 8, all in accordance with known practice.

'I'he shearing head 9 comprises a stationary cutter or comb I0, held in place by a securing means 4I l, and a movable cutter I2 reciprocative within said comb by aid of a rock-lever I3. This rock-leyer I3 is pivotally mounted on a fulcrum pin I'4, in the yoke l, and has oney end appropriately rounded at I5 for operative engagement in a suitable recess I6 in the base portion of the movable cutter l2; with the remote end appropriately forked at I1 for coaction with the special eccentric cam I8, of this invention, in turn rigidly xed on or formed integral with the drive-shaft 6. As best understood from Figs. 3.

shape, or preferably embodies three corresponding curvatures I9, and 2i, theY first two of which function as camming faceswhile the third is alwaysa dwell, and each of said faces is of a radius common to that lof an .arc struck from the axis of rotation 22, of the shaft t, with interveningcurvatures23, 24 and 25 also of a radius common to that struck fromthe axis of rotation 22; while the first of which 23 opposing the curve 2| always serves as a dwell, whereas 24 and 25 function for decelerating purposes as hereafter explained.

with flanking 30 angle portions effective as accelerating and decelerating arcs, according to the direction of rotation imparted to the cam I8. For example, assuming the cam I8, Fig. 3 is to rotate counterclockwise; as indicated by the arrow 26, the fork I1 remains unaffected or stationary until the tangential commencement of the active curvature I9 coacts with the confronting face 21 of said fork, whereupon'the lever I8 is rocked on the pin I4 with a gradual accelerating movement until the point of tangential mergence of the curvature I9 into the curvature 25 is reached, and, as said curvature coacts with the fork face 21, a decelerating movement of the fork I1 4takes place until the corresponding tangential meeting point of the curvature 25 with the dwell 2I takes place when the cyclic operation just de- In other words, the curvatures I 9 and 2li each comprise a camming angle of 60.

.4 and 8, the eccentric cam I8 .is of a special Fig. 9 diagrammatically indicates the to-'andfro strokes of the cutter blade I2 as effected by the cam curvatures I9, 28 and 2l, 25l relative to a degree chart 30 for one complete revolution-4 of the drive-shaft 8.- In other words, commencing from the central zero line 3 I, it will be understond that when the shaft 8 is rotated in either direction, there will be an initial 30 dwell period 32 of the fork I1 and cutter I2, as shown in Figs. 1-5, or rest for the cutter I2 of Figs. 6-8, during thefirst 30, rotary motion of said shaft. This dwell period 32 issucceeded by a 60 period of gradual and substantially-increasing accelerative movements 83, respectively; which movement' is succeeded by a 60 decelerating period 84 and a dwell of 30 to complete each half-revolution of the drive-shaft 6. From the cyclic opl eration just explained, it will be evident that scribed ceases. As the cam I8 continues rotation Vsaid fork inya reverse direction to that above set forth, or towards the right-hand in Fig. 3, until the tangential point of mergence of the curvature 25 into the dwell 2I is reached. Consequent upon the cyclic movements imparted to the fork end I1 of the rock lever I3 and the coaction of its rounded end I5 in the cutter recess I8, it -will now be clearly` apparent that the rotary movement of when the camV I8 is inthe position shown in Fig.

3, the rock-lever I3 is at rest, with the movable cutter I2 located as illustrated in Fig. 5, and that both said lever and said cutter will so remain unaffected during the. first 30 rotary movement 32o! the drive-shaft "6. As further movement of thecam I8 takes place in'th direction of the .arrow 28, the cutter I2 will move towardsv the right-hand in Fig. 5 under the accelerative movev the dOt-and-dash line .Showing .I8 in Fig. 5. In

other words, the removal of the .hair during the dry shave is effectedl by aid of the means of thisv invention, while the movable cutter I2 is being lmore rapidly accelerated for a portion of, its

stroke than heretofore accomplished with known shavers of analogous type. 'I'his feature is readily the cam I8 is translated into sharp acceleratedecelerate reciprocation of the Vcutter I2, with intervening "dwells of substantial duration; or one complete revolution of the cam I8 affords two equal 120 periods of activity with an equal degree period of inactivity. In other words, the cutter I2 is moved to-and-fro, or in reverse directions, relative to the stationary cutter or comb.

I8, once during each complete rotation of the cam I8. When the drive of the shaft 8 is clockwise,

the cyclic functioning of the cam I8 will, obviously, be reversed to that above set forth.

Referring now to Figs, 6-8, inclusive, all parts corresponding with or having equivalents in the preceding disclosure are designated' by like reference characters, in order to dispense with uni -necessary repetitive description. It is to be remarked, however, that the drive shaft 8 extends into proximity with the movable cutter I2, which, in this form of the invention is `provided at the inner side with a rectangular recess 29 having the major dimensionvat right-angles to the axis of rotation 22 of the shaft 8. It is also noteworthy that the eccentric cam I8 is rigidlysecured to, or may be formed as an integral part of the shaft 6; `while its cyclic effect will be imparted direct to the movable cutter I2.

preciable "dwell" exists at either end of the rgspective' strokes. It is, accordingly, emphasized herein that with' the novelvcam I8 of this invention'a substantial dwell" is positively obtained at the end of each stroke of the movable cutter I2 which leaves the cutter gaps between the teeth 38, 81 full open and aords ample time for the hair to erect between said teeth, such erection being essential to proper severance and the obtaining of a clean shave devoid of repeatedstrokes on the part of the user. Also, it is to be particularly noted .that the novel cam I8 of this invention considerably increases the speed of the movable cutter I2 at the actual time of cutting or severing the hair; while it is not essential that,

the angular relation of the curvatures I8-2Iand cording to thel direction of rotation of the caml I drive. .Having thus described my invention, I claim:

1. In a power actuated shaving device including a drive shaft, and a movable cutter; an eccentric cam on said shaft, said cam being prefercurvature projecting wholly beyond such cir-4 cumferential contines yand always serving as a dwell; and means operatively coupling the cam to the movable cutter, whereby leach half-revolutiony of the former imparts consecutive accelerative and decelerative reciprocatorymovements to the latter of lmajor degree with initial and terminal dwell periods, of minor duration.

2. The combination of claim 1 wherein each cam face embodies a maior arc of the same radius with complemental' end arcs of equal minor radius, and one vof said camV facesfbeing posi,-

tioned so thatthe pointfrom which the major" arc, as well as thatv from which the opposing minor arc, isstruck both coincide with the axis l0 of rotation of the 1drive shaft.

' HANS J. znvriarnumirzN.v 

